scholarly journals Global atmospheric chemistry – which air matters

2017 ◽  
Vol 17 (14) ◽  
pp. 9081-9102 ◽  
Author(s):  
Michael J. Prather ◽  
Xin Zhu ◽  
Clare M. Flynn ◽  
Sarah A. Strode ◽  
Jose M. Rodriguez ◽  
...  

Abstract. An approach for analysis and modeling of global atmospheric chemistry is developed for application to measurements that provide a tropospheric climatology of those heterogeneously distributed, reactive species that control the loss of methane and the production and loss of ozone. We identify key species (e.g., O3, NOx, HNO3, HNO4, C2H3NO5, H2O, HOOH, CH3OOH, HCHO, CO, CH4, C2H6, acetaldehyde, acetone) and presume that they can be measured simultaneously in air parcels on the scale of a few km horizontally and a few tenths of a km vertically. As a first step, six global models have prepared such climatologies sampled at the modeled resolution for August with emphasis on the vast central Pacific Ocean basin. Objectives of this paper are to identify and characterize differences in model-generated reactivities as well as species covariances that could readily be discriminated with an unbiased climatology. A primary tool is comparison of multidimensional probability densities of key species weighted by the mass of such parcels or frequency of occurrence as well as by the reactivity of the parcels with respect to methane and ozone. The reactivity-weighted probabilities tell us which parcels matter in this case, and this method shows skill in differentiating among the models' chemistry. Testing 100 km scale models with 2 km measurements using these tools also addresses a core question about model resolution and whether fine-scale atmospheric structures matter to the overall ozone and methane budget. A new method enabling these six global chemistry–climate models to ingest an externally sourced climatology and then compute air parcel reactivity is demonstrated. Such an objective climatology containing these key species is anticipated from the NASA Atmospheric Tomography (ATom) aircraft mission (2015–2020), executing profiles over the Pacific and Atlantic Ocean basins. This modeling study addresses a core part of the design of ATom.

2017 ◽  
Author(s):  
Michael J. Prather ◽  
Xin Zhu ◽  
Clare M. Flynn ◽  
Sarah A. Strode ◽  
Jose M. Rodriguez ◽  
...  

Abstract. An approach for analysis and modeling of global atmospheric chemistry is developed for application to measurements that provide a tropospheric climatology of those heterogeneously distributed, reactive species that control the loss of methane and the production and loss of ozone. We identify key species (e.g., O3, NOx, HNO3, HNO4, C2H3NO5, H2O, HOOH, CH3OOH, HCHO, CO, CH4, C2H6, acetaldehyde, acetone), and presume that they can be measured simultaneously in air parcels on the scale of a few km horizontally and a few tenths vertically. Six global models have prepared such climatologies (at model resolution) for August with emphasis on the vast central Pacific and Atlantic Ocean basins. We show clear differences in model generated reactivities as well as species covariances that could readily be discriminated with an unbiased climatology. A primary tool is comparison of multi-dimensional probability densities of key species weighted by frequency of occurrence as well as by the reactivity of the parcels with respect to methane and ozone. The reactivity-weighted probabilities tell us which parcels matter in this case. Testing 100-km scale models with 2-km measurements using these tools also addresses a core question about model resolution and whether fine-scale atmospheric structures matter to the overall ozone and methane budget. A new method enabling these six global chemistry-climate models to ingest an externally-sourced climatology and then compute air parcel reactivity is demonstrated. Such an observed climatology is anticipated from the NASA Atmospheric Tomography (ATom) aircraft mission (2015–2020), measuring the key species, executing profiles over the Pacific and Atlantic Ocean basins. This work is a core part of the design of ATom.


2003 ◽  
Vol 54 (4) ◽  
pp. 463 ◽  
Author(s):  
Wade Whitelaw

Gamefishing is a developing industry for many of the Pacific Island nations, with a number of countries encouraging the industry with tax relief and tourism promotion. This paper was prepared to provide a preliminary appraisal of gamefish facilities and recreational billfish catches of Pacific Island countries in the Western and Central Pacific Ocean. The level of development of gamefishing varies among Pacific Island nations, with fishers of some countries only carrying out subsistence fishing (including billfish), whereas others have a well-developed gamefishing infrastructure. The gamefish facilities of each country are described, including charter operations, number of private vessels and berthing facilities. Estimates of recreationally caught billfish are also provided for each Pacific Island nation. These estimates have been facilitated by the development of a gamefish catch and effort database by the Secretariat of the Pacific Community. Presently, an estimated 1050 metric tonnes of marlin are caught by gamefishing in the Western and Central Pacific Ocean, which compares with an estimate of around 18 000 metric tonnes caught by commercial longline and purse seine vessels.


ZooKeys ◽  
2019 ◽  
Vol 883 ◽  
pp. 1-82 ◽  
Author(s):  
Helena Wiklund ◽  
Lenka Neal ◽  
Adrian G. Glover ◽  
Regan Drennan ◽  
Muriel Rabone ◽  
...  

We present DNA taxonomy of abyssal polychaete worms from the eastern Clarion-Clipperton Zone (CCZ), central Pacific Ocean, using material collected as part of the Abyssal Baseline (ABYSSLINE) environmental survey cruises ‘AB01’ and ‘AB02’ to the UK Seabed Resources Ltd (UKSRL) polymetallic nodule exploration contract area ‘UK-1’, the Ocean Mineral Singapore exploration contract area ‘OMS-1’ and an Area of Particular Environmental Interest, ‘APEI-6’. This is the fourth paper in a series to provide regional taxonomic data with previous papers reporting on Cnidaria, Echinodermata and Mollusca. Taxonomic data are presented for 23 species from 85 records within four polychaete families: Capitellidae, Opheliidae, Scalibregmatidae and Travisiidae, identified by a combination of morphological and genetic data, including molecular phylogenetic analyses. Two taxa (genetically separated from one another) morphologically matched the same known cosmopolitan species,Ophelina abranchiatathat has a type locality in a different ocean basin and depth from where no genetic data was available. These two species were assigned the open nomenclature ‘cf.’ as a precautionary approach in taxon assignments to avoid over-estimating species ranges. Twelve (12) taxa are here described as new species,Ammotrypanella keenanisp. nov.,Ammotrypanella kerstenisp. nov.,Ophelina curlisp. nov.,Ophelina ganaesp. nov.,Ophelina juhazisp. nov.,Ophelina martinezarbizuisp. nov.,Ophelina meyeraesp. nov.,Ophelina nunnallyisp. nov.,Oligobregma brasieraesp. nov.,Oligobregma tanisp. nov.,Oligobregma whaleyisp. nov.andTravisia ziegleraesp. nov.For the remaining nine taxa, we have determined them to be potentially new species, for which we make the raw data, imagery and vouchers available for future taxonomic study. The CCZ is a region undergoing intense exploration for potential deep-sea mineral extraction from polymetallic nodules. We present these data to facilitate future taxonomic and environmental impact study by making both data and voucher materials available through curated and accessible biological collections.


Zootaxa ◽  
2020 ◽  
Vol 4748 (1) ◽  
pp. 163-181 ◽  
Author(s):  
JOHANNA N. J. WESTON ◽  
PRISCILLA CARRILLO-BARRAGAN ◽  
THOMAS D. LINLEY ◽  
WILLIAM D. K. REID ◽  
ALAN J. JAMIESON

Eurythenes S. I. Smith in Scudder, 1882 are one of the largest scavenging deep-sea amphipods (max. 154 mm) and are found in every ocean across an extensive bathymetric range from the shallow polar waters to hadal depths. Recent systematic studies of the genus have illuminated a cryptic species complex and highlighted the benefits of using a combination of morphological and molecular identification approaches. In this study, we present the ninth species, Eurythenes plasticus sp. nov., which was recovered using baited traps between the depths 6010 and 6949 m in the Mariana Trench (Northwest Pacific Ocean) in 2014. This new Eurythenes species was found to have distinct morphological characteristics and be a well-supported clade based on sequence variation at two mitochondrial regions (16S rDNA and COI). While this species is new to science and lives in the remote hadal zone, it is not exempt from the impacts of anthropogenic pollution. Indeed, one individual was found to have a microplastic fibre, 83.74% similar to polyethylene terephthalate (PET), in its hindgut. As this species has a bathymetric range spanning from abyssal to hadal depths in the Central Pacific Ocean basin, it offers further insights into the biogeography of Eurythenes. 


2007 ◽  
Vol 22 (1) ◽  
pp. 125-142 ◽  
Author(s):  
Transform Aqorau

AbstractThe 2000 Convention for the Conservation and Management of Highly Migratory Fish Stocks in the Western and Central Pacific Ocean (WCPF Convention) establishes a Commission which will be responsible for setting catch limits and effort controls for the fishery. The Convention will require the Pacific Island States to impose some form of catch limits and this presents them with the opportunity to explore ways to enhance the fisheries regimes they manage. This paper explores the legal issues surrounding a possible rights-based regime, both as a collective approach by the Pacific Island States, and individually. The paper suggests possible legal approaches to the introduction of a rights-based fisheries management regime, drawing on ways in which they may structure their fisheries legislation, and on experiences from other regions. The paper concludes by examining the implications for the Pacific Island States of such an approach.


1941 ◽  
Vol 35 (3) ◽  
pp. 443-461 ◽  
Author(s):  
Beatrice Orent ◽  
Pauline Reinsch

Recently, certain small uninhabited islands in the central Pacific Ocean have assumedsudden importance for the British Empire and the United States. Their value as landing places for commercial aviation and as strategic bases for air and naval forces is being increasingly recognized. Acquired during the past century by Great Britain and the UnitedStates, many of these islands have been the object of conflicting claims to sovereignty by the two nations. To clarify their status, it has been found desirable to review the past practice of these states and to examine those factors which were considered adequateto create sovereign rights over uninhabited islands in the Pacific.


2020 ◽  
Author(s):  
Andréa S. Taschetto ◽  
Caroline C. Ummenhofer ◽  
Malte F. Stuecker ◽  
Dietmar Dommenget ◽  
Karumuri Ashok ◽  
...  

<p>The warming of the equatorial Pacific associated with the El Niño–Southern Oscillation (ENSO) causes profound impacts on rainfall and temperature in the tropics and extratropics. El Niño drives changes in the Walker and Hadley circulations, warms the tropics and affects the neighboring ocean basins, favoring a short-term rise in global temperatures. We will present an overview of the atmospheric teleconnections driven by ENSO and its diversity focusing on the impacts over land and remote ocean basins. During El Niño, dry conditions are generally observed in the Maritime Continent, northern South America, South Asia and South Africa, while wet weather typically occurs in southwestern North America, western Antarctica, and east Africa. Global effects during La Niña are overall the opposite to El Niño, however this assumption is not true for all regions. ENSO atmospheric teleconnections are non-linear in part due to different locations of the anomalous equatorial warming (Eastern versus Central Pacific events) superimposed on the Pacific mean state, as well as interactions with the annual cycle, off-equatorial regions, remote ocean basins, and other modes of climate variability. Adding to this complex behavior, ENSO teleconnections are non-stationary either due to deterministic low-frequency modulations or stochastic variability, the latter being a factor generally overlooked in the literature. As the world warms in response to greenhouse gas forcing, ENSO atmospheric teleconnections are expected to change, despite large uncertainties in ENSO projections. We will discuss the limitations of climate models in representing realistic teleconnections from the tropical Pacific to remote regions and some of the challenges for future projections.</p>


2011 ◽  
Vol 24 (19) ◽  
pp. 5192-5194 ◽  
Author(s):  
S. M. Penny ◽  
G. H. Roe ◽  
D. S. Battisti

Penny et al. recently showed that the midwinter suppression in storminess over the western and central Pacific Ocean is due to a reduction in the number and amplitude of “seed” disturbances entering the Pacific storm track from midlatitude Asia. In this reply, the authors strengthen the conclusions that were originally put forth and show that the apparent departure from this behavior presented in a recent comment originates in the commenters having undersampled the full dataset of interannual variability. It is shown that when the Pacific storm track is only weakly “seeded” by an upstream source, as is common during winter and uncommon during fall and spring, it is likely to be weaker than average, and this reduction is highly statistically significant and the amplitude compares well with the midwinter suppression.


2021 ◽  
pp. 485-544
Author(s):  
Jason S. Link ◽  
Anthony R. Marshak

This chapter describes the West Pacific region and the major issues facing this marine fisheries ecosystem, and presents some summary statistics related to the 90 indicators of ecosystem-based fisheries management (EBFM) criteria. The U.S. Western Pacific region composes over half (~51%) of the U.S. Exclusive Economic Zone (EEZ), including multiple remote archipelagos, and extends over much of the Western and Central Pacific Ocean basin. The Western Pacific contains the second-highest (among eight regions) number of managed taxa in U.S. waters, including commercially and recreationally important bottomfishes (e.g., emperors, snappers, groupers), pelagic fishes, crustaceans, corals, and coral reef-associated taxa. The U.S. Western Pacific has been affected by above-average natural and human stressors that include the highest frequency and intensity of cyclonic storm activity, intensive fishing, high coastal development, and continually increasing temperatures. Overall, significant EBFM progress has been made in terms of implementing ecosystem-level planning and advancing knowledge of ecosystem principles.


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